Jounce bumpers are often mounted on a vehicle, as shown in U.S. Pat. No. 5,725,203, where the jounce bumper is free standing to prevent a control arm of the suspension from impacting with the vehicle frame.
Jounce bumpers can be mounted in a free state or with a rigid cup. Commonly assigned U.S. Pat. No. 6,158,726 discloses a jounce bumper with the use of a rigid cup that is designed to be attached to the vehicle frame. The rigid cup acts to attach the jounce bumper to the vehicle (or alternatively the strut) and limits the jounce bumper distortion, thereby increasing its spring rate. The force necessary to compress the jounce bumper increases as the jounce bumper is compressed and the jounce bumper absorbs energy as it is being compressed. As the jounce bumper is compressed, the resistance to compression increases to the point where the jounce bumper acts as a solid, and transfers the remaining energy from the impact to the vehicle. The use of a rigid cup or another constraint limits the bulging of the bumper, thereby reducing the amount of travel needed to reach the point where the bumper becomes a solid. In general, when more energy must be removed, a larger bumper is used.
In some applications, it is necessary to provide a taller bumper in order to limit motion of the suspension control arm. Yet, with a taller jounce bumper, sometimes it is also desirable to maintain the stiffer spring rate of a shorter jounce bumper. Accordingly, it is desirable to provide a jounce bumper that can be made to be taller while maintaining the stiffer spring rate of a shorter jounce bumper.